Circuit breaker



FIG. 1 is a front view of a circuit breaker showing my new design;

FIG. 2 is a top, front and left side perspective view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a rear view thereof; and,

FIG. 8 is a rear and lower left perspective view thereof. 

The ornamental design for a circuit breaker, as shown. 